High-grade cannabis grown in Washington, Oregon and Northern California is worth about $1,800 to $2,500 a pound locally. But in Chicago the price jumps to $5,000 a pound and can climb even higher on the East Coast, law enforcement officials say.

“The farther east you go, that price goes up and up and up,” said Deputy Joel Gorham, a crime interdiction officer with the Kootenai County Sheriff’s Office.

Clandestine farms and basement grow rooms are not the only source of this lucrative trade. Medical marijuana, too, is diverted to the black market. Growers easily can produce far more medical pot than state laws permit patients and designated providers to have, Gorham said.

“So what happens to all the surplus? It comes through here and it goes somewhere else where they can make a higher profit,” he said.

States are easing up on marijuana prohibitions. Eighteen now have medical marijuana laws, and voters in Washington and Colorado recently approved measures legalizing recreational use.

But the war on drugs is not letting up.

Local law enforcement agencies are seizing cash and cars in drug stops and pumping the money back into interdiction efforts – work they admit may be stopping only a small fraction of what’s moving down the road.

In Kootenai County, Gorham and his partner, Deputy Jerry Moffett, seized about 400 pounds of marijuana in 2012. They took about the same amount off drug runners over the previous two years combined.

In one of their largest busts, they stopped a pickup truck early last May and questioned the driver, a 58-year-old man who was trembling and more nervous than usual for a traffic stop.

Ronald Ray Clark, an Aspen, Colo., jeweler known by the nickname Diamond, consented to a vehicle search. Moffett opened one of two duffel bags in the bed of the truck and found marijuana in heat-sealed bags. The pot weighed in at 167 pounds.

Clark was charged with trafficking more than 25 pounds of marijuana, which in Idaho carries a mandatory minimum sentence of five years in prison. He pleaded not guilty and died about three months later in Aspen before he could be prosecuted.

The Idaho State Police patrol division is seeing a surge in marijuana seizures. In 2012, troopers confiscated more than 660 pounds in 45 traffic stops involving at least a pound of pot. Most of that was in the Boise area along Interstate 84, followed by the I-90 corridor in North Idaho.

In one stop last month, a trooper pulled 120 pounds of marijuana, with an estimated street value of $386,000, from an SUV caught speeding eastbound on I-90 near Pinehurst in Shoshone County. The driver, a 40-year-old illegal immigrant, was arrested and charged with felony trafficking.

The ISP was unable to identify the origin of nearly half of the marijuana in last year’s seizures. Of the drugs that could be identified, about 20 percent came from California, 13 percent from Oregon, 9 percent from Washington, 5 percent from Colorado and 4 percent from Montana – all states with medical marijuana laws.

Just how much is diverted from medicinal grow sites is hard to nail down, but investigations show more of the product is being funneled into the black market, said Capt. Charlie Spencer in ISP’s headquarters.

“They are bringing that marijuana into our state,” Spencer said. And with the decriminalization of marijuana possession in Washington and Colorado, “We are anticipating that these numbers are probably going to increase,” he added.

Seizures almost always from eastbound lanes

Mexican weed largely circulates in the South, selling for around $700 a pound. In the Northwest, cannabis cultivation is all about the high-potency marijuana that swept the scene with the explosion of “BC bud” out of British Columbia.

It’s premium stuff, and demand for it across the country feeds a constant supply chain from the West Coast. When police seize loads on I-90 and other drug corridors, it’s almost always in the eastbound lanes.

Washington State Patrol Trooper Nick Gerard, a K-9 officer based out of Spokane, primarily patrols the interstate with his black Lab, Kolohe. He sees the economics of drug trafficking at play.

“You make one run, take a shot at it … you’re going to get paid a lot of money if you can get that load through,” Gerard said. “And with the economic times we have now, people are willing to take that risk.”

Last spring he pulled over two middle-age women, with two children in the car, who admitted to having a couple of grams of pot on them. But Kolohe was drawn to a stronger scent in the trunk. Gerard got a search warrant and found 12 pounds of marijuana plus some hashish, a cannabis product.

The women, headed to Montana from California, were arrested on charges of possession with intent to deliver. They could have netted $15,000 to $20,000 if they had made it through.

“The black market for it is extremely big. It’s not going to go away,” Gerard said. “I’ve been doing this 23 1/2 years, and it’s as strong as it’s ever been.”

He also sees a surge in heroin moving through the area. The soaring cost of opioid painkillers such as oxycodone and hydrocodone has pushed many addicts to the similar but far cheaper high from heroin, Gerard said.

Moving drugs along interstates and highways is a relatively low-risk method of distribution, even with a growing emphasis on interdiction work.

Some traffickers use drug mules – a driver paid thousands of dollars to deliver a car concealing drugs to another state.

Others ship the drugs using the Postal Service and private mail services, which Gorham believes is a growing trend. Often the packages can’t be traced back to the sender.

“We’ve run into evidence in our stops that people have started out shipping a pound or two at a time, and eventually they get greedy and bring all their money over to buy a big load, and that’s when we pop them,” he said.

Another option is private aircraft.

“It’s nothing for a load of Ecstasy or marijuana to be loaded up in any of these places and driven into the Coeur d’Alene Airport,” Gorham said.

Up to 15 plants per person

Much of the black market marijuana from Washington is grown illegally – in remote corners of Eastern Washington on public and private lands, and in indoor grows on the West Side.

It can be difficult to tie marijuana seizures to specific medical dispensaries or growers, but investigations of traffic stops in other states indicate there is a robust underground trade in pot produced under the auspices of medicinal programs.

“It is being done. And we receive it anecdotally,” said Dave Rodriguez, director of the Northwest High Intensity Drug Trafficking Area, a federal program that assists law enforcement agencies in 14 Washington counties, including Spokane County.

Part of the problem, Rodriguez and others said, is how much marijuana a patient is entitled to in Washington and Oregon. The two states have the nation’s highest possession limits: 24 ounces and six mature plants per person in Oregon, and 24 ounces and 15 plants – defined as a 60-day supply – in Washington.

“You’d have to be smoking from sunup to sundown to be able to go through that much marijuana,” Rodriguez said. “The conclusion is that if you are growing to the limit, then it’s going to be diverted.”

“Each plant can produce up to a pound, if you know how to grow it correctly,” he said. “So what are they going to do with this (excess)? Are they just going to throw it away, are they going to burn it, throw it down the toilet? No. They know there’s a value behind it.”

It’s easy to manipulate the law for profit, said Gerard, with the WSP, and he sees it routinely in traffic stops.

“Every single day you can be in possession of a pound and a half in our state,” he said. “So you get two people in a car that both have their (medical authorization) cards. They load up with 3 pounds of marijuana, they go from Seattle to Spokane or try to make their way into North Idaho, and turn around and double their profits on a one-day run.”

Making several such runs a week can be quite lucrative, Gerard said. “They’re making $20,000 a month untaxed. They’re living a pretty good life,” he said.

State oversight could address oversupply

The trade group for Washington’s self-regulated medical marijuana industry is pushing for changes in state law that will help bring production and distribution out of the shadows, said Greta Carter, executive director of the Coalition for Cannabis Standards and Ethics.

“The more that cannabis can be routed into legitimate markets, where we can tax and we can regulate and control it, the less appealing the underground economy becomes,” Carter said.

The Legislature last year passed a bill to set clearer regulations on medical marijuana use and establish a licensing system and patient registry to protect qualifying patients, doctors and providers from criminal liability. But Gov. Chris Gregoire vetoed critical parts of it – including regulations for dispensaries and producers – over concerns that state workers still could be prosecuted under federal law.

Lawmakers plan to take another run at the reforms this year, at the same time the state confronts the reality of the new recreational use law.

Voters in November approved an initiative to decriminalize and regulate the possession of an ounce or less of marijuana by adults over 21. The measure calls for setting up state licensing procedures for pot growers, processors and retail stores, with the marijuana taxed 25 percent at each stage.

Carter, who once operated a medical marijuana dispensary in Spokane, said state oversight of both medicinal and recreational marijuana will resolve questions about surplus supplies.

“Are there going to be bad actors out there that are motivated by greed or have been in the underground economy for so long they don’t want to come forward? Yes. And do we need to weed them out? I’m the first one there to report them,” she said. “If somebody’s not playing by the rules, yes, get them out.”

‘We’re talking major crime here’

Officers working the I-90 drug corridor are apprehensive about the increasing acceptance of marijuana. As long as considerably more money can be made trafficking drugs than supplying legal markets, they say, people will be drawn into it.

Authorities also worry about more drug-related crime, including home-invasion robberies targeting marijuana suppliers, and maybe even reprisals from crime syndicates.

“All of a sudden Washington has gotten in the business of distributing marijuana, and that is going to cut into a business enterprise, the drug cartels,” Moffett said, adding that he is fearful of the violence that may arise. “These people are all about money.”

Idaho now borders four medical marijuana states, but medical marijuana cards are worthless in the Gem State. No amount of marijuana is legal to possess in Idaho, and the state’s penalties for felony possession are stiffer than federal sentences.

To get across the Idaho Panhandle, traffickers need to traverse just 75 miles of interstate. But it’s not clear sailing.

In an effort to disrupt the flow of drugs and money through Kootenai County, the Sheriff’s Office formed the criminal interdiction unit in 2010.

The deputies are trained to look for certain cues that tip them off to criminal activity. Nervous behavior is one of the best indicators.

“It’s something that people can’t control at all,” Gorham said. “They just give themselves away.”

Local crime response remains the department’s priority, and Moffett and Gorham regularly are pulled off their patrol to work other cases, said Capt. Dan Soumas, patrol commander.

“But we do have an obligation to not just turn a blind eye” to what’s moving along the interstate, he said. “And we’re talking major crime here.”

“There’s a whole lot of crime happening outside our jurisdiction; we just happen to be the funnel point they’re passing through,” Soumas said.

The lure of easy money draws all types into trafficking drugs. They’ve arrested drug traffickers as young as 18 and as old as 67, almost all of them men. The portrait, however, is no more specific than that.